I’ve had this floating around in my mind ever since I started working full-time, but I say “got it” now when people explain things to me. I typically never externally acknowledged if I knew exactly or had no idea what the hell the other person was saying to me. Now, when my coworkers explain something to me, I say “got it”. I think it’s out of the desire to communicate that I’m paying attention or that I’m not a dumbass potato. Anyway.